New Brakes for '06 A4

[dcaron9999]

Re: New Brakes for '06 A4

My new brakes are akebonos euro and zimmerman coated rotors. I bled my brakes again, using Bentley Publisher procedure this time. (29 psi from pressure bleeder ,pumped and held brake pedal with prop, bled from closest wheel to furthest wheel). Saw some tiny bubbles escape the calipers. Went for another test drive, and to bed the brakes again. Pedal is slighty firmer , brakes smoother, and have more bite . I still find that the pedal travel is a bit excessive.

[PRY4SNO]

Re: New Brakes for '06 A4

Sounds like textbook Audi brakes...

+1 for the s/s lines.

[dcaron9999]

Re: New Brakes for '06 A4

Sounds like textbook Audi brakes...

+1 for the s/s lines.

Thanks. Do they really make a difference, or are they just cosmetics?

[onceover]

Re: New Brakes for '06 A4

Read my post

[dcaron9999]

Re: New Brakes for '06 A4

Was the pedal more firm prior to the bleeding or were you hoping to increase the firmness? If its the latter, I would suggest looking into some stainless braided lines as they deform less under pressure and help stiffen up the pedal

If I recall correctly, the pedal was slightly more firm before I did the brakes. Ever since I got the 2005 allroad about 2 months ago, I was never impressed by the stopping power and pedal firmness. Having said that, the brakes were not in good shape (lots of rust and unequal wear on the rotors, thin front pads, etc). I figured that after I do a thourough brake job (replacement, cleaning, lubrication, and bleeding) I would get much better brake pedal response, and braking power.

I will look into new lines, but was also wondering if this is the default behavior of stock allroad brakes which I should expect, being a new allroad owner. Ive owned/driven lots of pre-owned BMW cars and SUVS, and the braking power + pedal feal is in another league. My other car is a 2002 BMW 330xi (E46 chassis) with stock brakes and rotors - perhaps the comparison is not fair ... ;-)

[PRY4SNO]

Re: New Brakes for '06 A4

Yeah... BMW brakes have a light-switch kind of feel for engagement. Even after I upgraded to Brembos on my coupe they don't feel half as sensitive as an e92 330i.

I'd say get the lines anyways (rubber wears out in a few years with microfissures you can't see but open enough under pressure to allow moisture into the fluid) and go from there. Looks like you have a lot of bleeding in your future. haha

If you're that skeptical, you could try and find another member with an AR you could take for a spin to compare.

[dcaron9999]

Re: New Brakes for '06 A4

Ive used the traditional bleeding method once more this afternoon. This time, I used both the Motive Power Bleeder with 29PSI, in combination with pumping the pedal, and pumping the hand brake. I noticed minute bubbles from the rear calipers, with my shop LED light an inch away from the flush tube. I went through 2 liters of DOT 4 fluid, until a steady stream of "bubble/foam free" liquid appeared. The front calipers did not show signs of bubble, but I still pumped the pedal and ensured constant pressure from the power bleeder.

Three bleed cycles so far in five days, and Im gaining some pedal firmness/height each time. I still think the pedal travel is too much. Im not re-assured that braking power is enough in an emergency braking situation.

Im might give up now and bring the car to a certified mechanic. I spoke to an VW/Audi mechanic today, he suggested troubleshooting the problem this way: with the egine running, pinch each caliper flexible rubber tube one at a time, and see if the brake pedal becomes firm. If it does, I may have a damaged caliper.

[Natty54]

Re: New Brakes for '06 A4

Could try that. Did you look at your lines? any cracks? as mentioned earlier they could be expanding. Are you leaking fluid anywhere?

If you are still getting air after 3 bleed cycles and doing it properly there has to be a leak somewhere. Are you tightening the bleed valves all the way? Only other thing I can think of is a faulty master cylinder which would also relate to a spongy pedal

[dcaron9999]

Re: New Brakes for '06 A4

I did not inspect the flexible lines. I doubt I have a leak as my fluid reservoir stays at the Max level. No sign of liquid leaks anywhere. I closely inspected the reservoir and the Brake booster up close too today too. I tighten the valves tightly each time, to the point I almost stripped one of them.

Perhaps the lines or booster is at fault as you mentioned, but I was hoping not to throw parts at the problem, and revert to trial and error. I heard that if the system has not been opened, and reservoir never ran dry, I should not have to bleed ABS unit via VCDS or other external diagnotics tool. So I tried multiple approaches to bleeding the brakes.


For now, Ive pulled my hand brake to its uppermost position, and jammed a piece of wood between my pedal and my seat overnight. I removed the brake light fuse to avoid draining the battery. Will test tomorrow am, and bleed the old-fashioned way (two persons) if I need to.

I thought I would mention that the pedal gets rock hard after two presses when the engine is off, but softens and sinks down as soon as I start the engine. Dont know if this may be a hint to finding the root cause ...

[dcaron9999]

Re: New Brakes for '06 A4

Did the zeckhausen bedding procedure twice, before realizing the instrutions that came with the pads (Akebonos Euro) said to drive easily for the 500Kms. Oops ...

Ive bled the brakes four times by myself, and once by a mechanic, to try to get rid of a spongy pedal. I need to sink the pedal close to the floor for hard braking, and to engage ABS. I bled the brakes with combination of a motive power bleeder, brake pedal pumping, including hitting the calipers with a rubber mallet to remove any air bubbles.

Im still not happy with the stopping power, but my mechanic said to be patient, as the pad wear and surface contact is not optimal yet. He disapproved of the bedding procedure I used, and said that I might have made things worse, by "glazing the rotors". He suggested that I lightly sand the rotors, and let the pads wear down gradually. If Im not happy after 500Kms or so, to get rid of the pads, and go back to OEM or better quality.

Any thoughts?

[PRY4SNO]

Re: New Brakes for '06 A4

Sounds like text book Audi brakes.

Like stepping on marshmallows.

[dcaron9999]

Re: New Brakes for '06 A4

Sounds like text book Audi brakes.

Like stepping on marshmallows.

I guess Im going to need to get used to that, but its tough when my other car is a 2002 BMW 330xi which has a rock hard pedal, and brakes that stop the car on a dime.

[PRY4SNO]

Re: New Brakes for '06 A4

I'll just leave this here...

[dcaron9999]

Re: New Brakes for '06 A4

^^^ Wish I could afford these, but they will cost me half of what I paid for the car....


Noticed today while sitting at a stop light, I must press the brake pedal until it is aligned with the gas pedal at idle, just to stop the car from moving. Is this normal behavior?

[dcaron9999]

Re: New Brakes for '06 A4

I think I actually solved my problem. The brake booster pushrod (sitting behind the brake pedal) needed a little adjustment, to allow it to exert longer stroke into brake booster. My allroad now stops after 1.5 inch pedal travel and what seems like less pedal effort.

Step #20 on this post was the solution. No need to dismount/dismantle anything ...
http://www.audizine.com/forum/showth...er-removal-DIY

This took a while to resolve, so thanks for your patience all your input!